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First thoughts: Huck down in Iowa

From Chuck Todd, Mark Murray, and Domenico MontanaroDES MOINES, IA -- Want further proof that negative advertising works? After nearly two weeks of Romney airing TV ads in the this state criticizing his records on immigration and crime, Huckabee's standing in Iowa has slipped, according to the latest MSNBC/McClatchy/Mason-Dixon poll. In the survey, Romney now leads Huckabee, 27%-23%, although it's within the 5% margin of error. They're followed by Thompson at 14%, McCain at 13%, and Giuliani and Paul tied at 5%. Three weeks ago -- before Romney began his contrast ads -- the poll had Huckabee comfortably leading Romney, 32%-20%. One of the reasons for Huck's decline: His lead over Romney among self-identified born-again Christians has dropped from 42%-8% to 34%-27%. And among weekly churchgoers, it has decreased from 38%-15% to 28%-27%.

*** Dem race all about turnout: The Democratic race in Iowa, meanwhile, is essentially a three-way tie; just two points separate the three front-runners. In the poll, it's Edwards 24%, Clinton 23%, and Obama 22% -- followed by Richardson at 12% and Biden at 8%. Three weeks ago, it was Clinton 27%, Obama 25%, and Edwards 21%. Although the percentages in it show it to be a tossup, the poll suggests that turnout could decide the contest. According to the survey, Obama leads Edwards and Clinton among first-time caucus-goers, 31%-22%-21%. Among veteran caucus-goers, it's Edwards 25%, Clinton 24%, and Obama 18%. This suggests that a heavy turnout -- including many first-timers -- could greatly benefit Obama; a lighter turnout probably would benefit Edwards and (to a lesser degree) Clinton. Another important factor in the Dem contest is the battle for second choice (if a candidate doesn't clear the 15% viability threshold). In the poll, Edwards gets the most second-choice support, and when Richardson, Biden, Dodd, and Kucinich backers are realigned among the top three Dems, the poll has Edwards over Obama and Clinton, 36%-26%-26%.

*** Other interesting findings: Edwards has the highest fav/unfav score (73%-11%) among the Dem front-runners, while Clinton has the worst (59%-19%). On the GOP side, Romney has the highest rating (58%-19%), while both Giuliani (30%-39%) and Paul (21%-44%) have net-negative scores. In fact, this is the second-straight MSNBC/McClatchy poll that has Paul with a net-negative rating, leading us -- once again -- to wonder if Paul is running for the wrong party's nomination. The new poll was conducted from December 26-28 among 400 likely GOP and 400 likely Dem caucus-goers, and it has a 5% margin of error.

*** So what about tea leaves? This poll indicates that the candidate with the greatest upside on the Dem side is Edwards. He's polling competitively and has the highest ceiling of support among these likely caucus-goers; he's tops among second choice AND he's got the highest fav rating. Obama appears to have the next highest ceiling, with Clinton with the smallest room to grow, as she trails badly in second choice and her fav rating -- while excellent -- is third among the top three candidates. As for the tea leaves on the GOP side, Romney appears to have the big Mo; these numbers match the anecdotal we've picked up.

*** Should the Dems go negative, too? Will Romney's apparent success in going negative change the CW about negative ads in Iowa on the Dem side? Maybe not. Why? It's much easier to go negative in a two-way race than in a three-way one, and that's why you aren't seeing any of the Dems risk going negative for fear that if candidate A attacks candidate B, candidate C gains.

*** The Outsiders: Both Huckabee and Edwards are running against bigger bankrolls and it's pushed both to using populist appeals. But the two aren't just "outsiders" in the literal sense. They are also relying on "outsiders" to win Iowa. Both are getting arguably more support (in the case of Huckabee) or as much support (in the case of Edwards) from these groups. Obama is trying to make this an issue with Edwards, as the Obama camp sees these outside groups allowing Edwards to apparently outspend Obama in these final days on TV. These Obama hits are having -- potentially -- a divisive effect on SEIU, whose state and local affiliates are helping to bankroll one of these pro-Edwards groups. Should Edwards fail to win Iowa, don't be surprised if there is a lot of internal turmoil inside of SEIU. Last night, the national union sent out a release reaffirming its support for the pro-Edwards 527, which is making a lot of pro-Obama SEIU forces upset.

*** The electability primary: Interestingly, all three leading Dem candidates made electability pitches during their Iowa stops. What did they all see in their recent tracking? Or is this about wooing second choicers? After all, according to the MSNBC/McClatchy poll out today, 20% are supporting Richardson and Biden, making the second-choice vote very important. And electability likely is a greater concern among folks making a backup pick. It can be a deal closer.

*** On the trail: Once again, nearly everyone is in the Hawkeye State… Biden travels to Mason City, Garner, Algona, and Woodbury; Clinton attends church in Des Moines before going to Vinton, Traer, Cedar Falls, and Iowa Falls; Dodd hits Le Mars, Emmetsburg, and Mason City; Edwards campaigns in Boone, Denison, Mapleton, and Sioux City; Huckabee has no other public events but a jog; Obama appears in Knoxville, Newton, Indianola, and Des Moines; Richardson stumps in Marshalltown, Des Moines, and Fort Dodge; Romney hits Iowa City, Mount Vernon, and Moscow; and Thompson is in Ames and Webster City. Elsewhere, both Giuliani and McCain campaign in New Hampshire.